Portable electronic devices such as mobile telephones, laptop computers, music players, personal digital assistants and GPS devices may be provided with a housing inside which inter alia electronic components are arranged. The housing often comprises various buttons such as keypads and navigation buttons. In the housing of a portable electronic device there is often mounted a display. It is also common that the housing is provided with one or more connection sockets for connecting e.g. a battery charger, headphones, memory devices, etc.
Housing portions such as body shells, body shell parts, lids and buttons of portable electronic devices may be manufactured from a plastic material or from a metal. Plastic materials may have an advantage in that they may be cheap and easily formed into desired shapes whereas they may have inferior wear properties. Metallic materials may have greater resistance to wear than plastic materials whereas forming may be more difficult than with plastic materials. Metal housing portions may also have a higher weight than a plastic housing portion of similar size.
Housing portions may be also manufactured from a combination of a plastic material and a metal, i.e. a housing portion may comprise a plastic layer and a metal layer. For instance an outer layer of a housing portion may be formed by a metal layer, which may be supported by an inner plastic layer. The outer metal layer may provide a wear resistant, robust and exclusive feel to a particular housing portion.
The metal layer of a housing portion may be shaped in a pressing operation using a mechanical or hydraulic press. Also an outer texture or surface profile of the metal layer may be shaped in the pressing operation. However, finer surface textures may be achieved in a subsequent cutting operation, such as a milling or grinding operation.